3 ms·

We already have lots of data. Here's the Lancet paper: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext https://www.thelancet

by DanBC 6y ago

We already have lots of data. Here's the Lancet paper: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6... > Our search identified 172 observational studies across 16 countries and six continents, with no randomised controlled trials and 44 relevant comparative studies in health-care and non-health-care settings (n=25 697 patients). Transmission of viruses was lower with physical distancing of 1 m or more, compared with a distance of less than 1 m (n=10 736, pooled adjusted odds ratio [aOR] 0·18, 95% CI 0·09 to 0·38; risk difference [RD] −10·2%, 95% CI −11·5 to −7·5; moderate certainty); protection was increased as distance was lengthened (change in relative risk [RR] 2·02 per m; pinteraction=0·041; moderate certainty). Face mask use could result in a large reduction in risk of infection (n=2647; aOR 0·15, 95% CI 0·07 to 0·34, RD −14·3%, −15·9 to −10·7; low certainty), with stronger associations with N95 or similar respirators compared with disposable surgical masks or similar (eg, reusable 12–16-layer cotton masks; pinteraction=0·090; posterior probability >95%, low certainty). Eye protection also was associated with less infection (n=3713; aOR 0·22, 95% CI 0·12 to 0·39, RD −10·6%, 95% CI −12·5 to −7·7; low certainty). Unadjusted studies and subgroup and sensitivity analyses showed similar findings. The important bit here (for everyone saying we have great evidence that masks work) is that "low certainty" bit. That's GRADE, and it means "low certainty (our confidence in the effect estimate is limited; the true effect could be substantially different from the estimate of the effect);" So, maybe masks are substantially less, or more, protective.

ceejayoz 6y ago
Like I said, I'm not doing the dance again. Last time it was pointed out "low certainty" doesn't mean what you imply it does (https://news.ycombinator.com/item?id=23434344 https://news.ycombinator.com/item?id=23434344) you let it sail on by.
- DanBC 6y ago
  Here's what low certainty grade results mean: "low certainty (our confidence in the effect estimate is limited; the true effect could be substantially different from the estimate of the effect);". Just so we're clear: you've never linked to research to support any of your points, because you're not able to, are you?
  - ceejayoz 6y ago
    > Just so we're clear: you've never linked to research to support any of your points, because you're not able to, are you? I did. 28 days ago. https://news.ycombinator.com/item?id=23434255 https://news.ycombinator.com/item?id=23434255 https://news.ycombinator.com/item?id=23434053 https://news.ycombinator.com/item?id=23434053 > Here's what low certainty grade results mean: "low certainty (our confidence in the effect estimate is limited; the true effect could be substantially different from the estimate of the effect);". You're acting like its definition is "it's probably the opposite, and thus is evidence for my argument".
    - DanBC 6y ago
      And last time you posted those links I pointed out that they were for the same paper and the paper doesn't support your point. Here's someone explaining what GRADE means: https://twitter.com/dnunan79/status/1269014574478626819 https://twitter.com/dnunan79/status/1269014574478626819 "I teach GRADE If something has “low quality” evidence, it means the observed estimate is highly likely to be different from the truth. Face masks = low quality evidence. So what’s the point of GRADE if we can conclude “evidence shows”?" EDIT: Your link even says this > Further high-quality research, including randomised trials of the optimum physical distance and the effectiveness of different types of masks in the general population and for health-care workers' protection, is urgently needed
      - ceejayoz 6y ago
        OK, so let's apply these standards to you. You state here: https://news.ycombinator.com/item?id=23728926 https://news.ycombinator.com/item?id=23728926 > If you have the correct behaviour (hand washing, distancing) the mask provides you no benefit. Do you have a RCT with a high or at least moderate confidence/certainty finding backing that assertion up?
        DanBC 6y ago
        No, I'm tired of playing your stupid games. You've failed to post a link that supports any of your claims. The only link you posted directly contradicts your claim. Clearly, there's no point in me posting any links if you're going to misrepresent what they say. Cochrane have a bunch of research on masks and handwashing.

by DanBC 6y ago

ceejayoz 6y ago

Like I said, I'm not doing the dance again. Last time it was pointed out "low certainty" doesn't mean what you imply it does (https://news.ycombinator.com/item?id=23434344 https://news.ycombinator.com/item?id=23434344) you let it sail on by.

DanBC 6y ago
Here's what low certainty grade results mean: "low certainty (our confidence in the effect estimate is limited; the true effect could be substantially different from the estimate of the effect);". Just so we're clear: you've never linked to research to support any of your points, because you're not able to, are you?
- ceejayoz 6y ago
  > Just so we're clear: you've never linked to research to support any of your points, because you're not able to, are you? I did. 28 days ago. https://news.ycombinator.com/item?id=23434255 https://news.ycombinator.com/item?id=23434255 https://news.ycombinator.com/item?id=23434053 https://news.ycombinator.com/item?id=23434053 > Here's what low certainty grade results mean: "low certainty (our confidence in the effect estimate is limited; the true effect could be substantially different from the estimate of the effect);". You're acting like its definition is "it's probably the opposite, and thus is evidence for my argument".
  - DanBC 6y ago
    And last time you posted those links I pointed out that they were for the same paper and the paper doesn't support your point. Here's someone explaining what GRADE means: https://twitter.com/dnunan79/status/1269014574478626819 https://twitter.com/dnunan79/status/1269014574478626819 "I teach GRADE If something has “low quality” evidence, it means the observed estimate is highly likely to be different from the truth. Face masks = low quality evidence. So what’s the point of GRADE if we can conclude “evidence shows”?" EDIT: Your link even says this > Further high-quality research, including randomised trials of the optimum physical distance and the effectiveness of different types of masks in the general population and for health-care workers' protection, is urgently needed
    - ceejayoz 6y ago
      OK, so let's apply these standards to you. You state here: https://news.ycombinator.com/item?id=23728926 https://news.ycombinator.com/item?id=23728926 > If you have the correct behaviour (hand washing, distancing) the mask provides you no benefit. Do you have a RCT with a high or at least moderate confidence/certainty finding backing that assertion up?
      - DanBC 6y ago
        No, I'm tired of playing your stupid games. You've failed to post a link that supports any of your claims. The only link you posted directly contradicts your claim. Clearly, there's no point in me posting any links if you're going to misrepresent what they say. Cochrane have a bunch of research on masks and handwashing.